This invention relates to a wood chipping machine optionally capable of also simultaneously bagging chips, and particularly to a lightweight machine effective to chip not only brush and tree prunings but also larger diameter wood, using a small engine, and if desired to directly containerize the chips by power of the chipper.
A variety of wood chipping machines have been developed over the years for accommodating materials ranging in size from whole trees as in U.S. Pat. Nos. Re. 31,048 and 4,078,590 to brush as in U.S. Pat. No. 3,861,602. The latter type machine has proven highly effective and dependable for chipping brush and small trees, and consequently is widely employed by municipal crews, commercial tree services, landscapers and the like for converting large and small branches and even smaller trees into chips. The chips are typically blown from the chipper through a discharge chute at high velocity into an awaiting trailer, or truck, or often onto the ground. Although this machine can also be used for chipping the large volume of annual tree prunings produced when fruit and nut trees are pruned, or by smaller landscapers, the basic construction of this prior machine renders it more heavy duty than needed for such use, generally too costly to be economically feasible for many such operators, and sometimes too large, bulky and/or physically heavy to be moved along the work area, e.g. along rows of trees. A chipper for orchards and grooves must be capable of quick and easy movement from tree to tree to tree hundreds of times, to be able to quickly chip the 50-75 pounds or so of branches per tree. Up to the present time, it is understood that in states such as California hundreds of thousands of dollars have been spent seeking a solution to disposal of these annual prunings, but none has resulted. Thus, these are manually thrown into piles which are put into windrows and then pushed or hauled out of the grove or orchard for mass burning. Burning and landfill disposal of the prunings is being constantly further restricted because of pollution and the like.
Another disposal problem exists with respect to old lumber resulting from replacement every 15-25 years of exterior home structures such as decks and porches, and of downed or trimmed tree limbs and the like. Landfills do not allow or want them. Burning them is often outlawed. Trash trucks will usually not take them. Disposal is a real problem. Yet, the large engine of about 75-100 h.p. and accompanying heavy duty structure previously required to chip limbs and poles up to several inches in diameter place the price out of range for most potential users. The rule of thumb in the industry is that chipping of an eight inch diameter pole does require close to 100 h.p.
The chips resulting from such equipment are desirable for landscaping, mulch and the like. Prior brush chippers capable of handling these larger size poles and limbs, however, have a tendency when chipping brush to pull long strips or twigs through without cutting them into uniformly sized chips. Such long pieces or twigs are not attractive, are not as useful and tend to be greatly troublesome when attempts are made to bag the chips. These twigs prevent proper filling of the bags.
In addition to these larger brush chippers for commercial use, there have also been very small chippers as for back yard use. These typically are comparable in size to lawn mowers and have an infeed hopper for the twigs and small branches to be fed down to the chipper at a drop angle of about 37 degrees. These small chippers also tend to pull long pieces of branch and twigs through rather than chipping them. Bagging is a problem. Efforts have been made to prevent these long strips or twigs from being pulled past the anvil by the knife in prior chippers by setting the anvil close to the knife, but then the brush has a tendency not to feed well. If the anvil is backed off from the knife for more effective feeding, then the twigs are pulled through. And they are totally incapable of chipping anything large. Hence, they have not been widely adopted.
As to bagging of chips, some lawn mower size chippers or shredders that bag the product have been proposed heretofore, but these small devices are not deemed practical except perhaps for occasional backyard usage as by a homeowner. There are also large machines capable of just bagging previously cut chips. Such commercial baggers of chips are expensive, and moreover do not create the chips, but just bag them. Such prior apparatus has not enabled effective creation and usage of wood chips by landowners, gardeners, landscapers, etc. of millions of tons of prunings and cleanup branches and brush occurring each year.
There has existed a need for equipment capable of chipping trimmings such as the annual prunings from fruit and nut trees, without pulling long twigs or strips through the chipper, but also capable of chipping larger pieces up to six or eight inches in diameter if necessary.
A chipper of smaller horsepower, e.g. about 25 h.p., and smaller size and lighter weight than that of the present commercial brush chippers, would be particularly advantageous, especially if it could also bag the chips, and if it dependably cut even twigs into small chips rather than passing long pieces. Such a chipper should also be capable of chipping limbs and poles up to several inches in diameter without jamming the chipper, since these are frequently encountered in cleanup operations. It should be capable of constant use on a commercial basis, yet easy to use as by rental agency customers.